<!DOCTYPE html>
<script src="../../resources/testharness.js"></script>
<script src="../../resources/testharnessreport.js"></script>
<script id="target" type="module" src="resources/empty.js"></script>
<script>
var t = async_test('Makes sure that <script type="module"> preload resources');

target.onload = t.step_func(function() {
    if (window.internals === undefined) {
        throw new Error('This test requires internals.isPreloaded function.');
    }

    assert_true(internals.isPreloaded(target.src));

    var absoluteUrl = new URL(target.src, location.href).href;
    assert_equals(performance.getEntriesByName(absoluteUrl).length, 1,
                  'empty.js should load only once');
    t.done();
});
</script>
